Wed, 11 Nov 2015 09:06:30 +0100 | Andreas Lochbihler | add lemmas about monoids and groups | changeset | files |
Wed, 11 Nov 2015 15:41:01 +0100 | nipkow | tuned | changeset | files |
Tue, 10 Nov 2015 23:41:20 +0100 | wenzelm | recovered from a9c0572109af; | changeset | files |